- Elastography
Elastography is a non-invasive method in which stiffness or strain
image s ofsoft tissue are used to detect or classifytumors . A tumor or a suspiciouscancer ous growth is normally 5-28 times stiffer than the background of normal soft tissue. When a mechanical compression or vibration is applied, the tumor deforms less than the surrounding tissue. i.e. the strain in the tumor is less than the surrounding tissue.Medical Imaging
Ultrasonic imaging is the most common medical imaging technique for producing elastograms. Some research has been conducted using magnetic resonance elastography (MRE) and
computed tomography . However, using ultrasound has the advantages of being cheaper and faster than MRI techniques."Transient elastography" is used for example to measure the stiffness of the liver in vivo (FibroScan, Echosens, France). It is an alternative noninvasive method to
liver biopsy . A correlation between liver elasticity and the fibrosis score (orcirrhosis ) has been shown. [cite journal |author=Ganne-Carrié N, Ziol M, de Ledinghen V, "et al" |title=Accuracy of liver stiffness measurement for the diagnosis of cirrhosis in patients with chronic liver diseases |journal=Hepatology |volume=44 |issue=6 |pages=1511–7 |year=2006 |pmid=17133503 |doi=10.1002/hep.21420]Mathematical Description
Pre-compression images are correlated to post-compression images, resulting in regions of large and small change in position. This is called the shift-diagram. The derivative of the shift will produce the strain diagram.
References
External links
* [http://www.elastography.com University of Texas Elastography Research]
* [http://mayoresearch.mayo.edu/mayo/research/mri-lab/elastography.cfm Mayo Clinic Magnetic Resonance Elastography Research]
* [http://www.supersonicimagine.fr/ Supersonic Imagine]
* [http://www.echosens.com/ Echosens]
* [http://www.icr.ac.uk/press/press_releases_2001/3126.shtml/ Press release of potential uses of techniques developed by Dr. Bamber's elastography team at the Institute of Cancer Research in Sutton, UK]
* [http://www.medical.siemens.com/webapp/wcs/stores/servlet/SMStandardContentView~q_catalogId~e_-1~a_categoryId~e_12761~a_catTree~e_100010,1007660,12761~a_contentTypeId~e_1~a_langId~e_-1~a_pageId~e_80435~a_storeId~e_10001.htm Siemens Medical]
* http://www.emodeonline.com
* Real Time Elastography Hitachi [http://www.hitachi-medical-systems.co.uk/index.php?id=528]* http://www.hitachimed.com/specifications.asp?ID=1061#1699
* "Measurement of the Dynamic Shear Modulus of Mouse Brain Tissue In Vivo By Magnetic Resonance Elastography" [http://www.me.wustl.edu/faculty/pvb/bios/bayly%20papers/46.pdf]
* [http://www.me.wustl.edu/faculty/pvb/index.html Prof. Philip V. Bayly's research group at Washington University in St. Louis.]
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